How is Aluminum Made?

Aluminum originates as an oxide called alumina, and because aluminum itself does not occur in nature as a metal, the processing of aluminum took a giant leap forward with the advent of electricity.

Deposits of bauxite ore are mined and refined into alumina--one of the feedstocks for aluminum metal. Then alumina and electricity are combined in a cell with a molten electrolyte called cryolite. Direct current electricity is passed from a consumable carbon anode into the cryolite, splitting the aluminum oxide into molten aluminum metal and carbon dioxide.

The molten aluminum collects at the bottom of the cell and is periodically "tapped" into a crucible and cast into ingots or billets. While continual progress has been made over the more than 110-year history of aluminum processing to reduce the amount of electricity used, there are currently no viable alternatives to the electrometallurgical process.